Autonomous programming and adaptive filling of lap joint based on three-dimensional welding-seam model by laser scanning
Autonomous programming and adaptive filling of lap joint based on three-dimensional welding-seam model by laser scanning
复制标题
基于激光扫描三维焊缝模型的搭接接头自主编程与自适应填充
DOI：
10.1016/j.jmapro.2020.03.034
复制
发表时间：
2020-05-01
影响因子：
6.2
通讯作者：
Li, Zhuguo
中科院分区：
文献类型：
--
作者：
Yan, Minzhi;Zhang, Ke;Li, Zhuguo
传统的大型复杂结构焊接教学编程难度极大，效率低，一致性差，难以获得整个焊接路径上接头几何形状的随机变化和获得优异的焊接质量。提出了一种基于激光结构光扫描的焊接路径自动生成和搭接焊缝自适应填充的集成方法。首先，通过激光扫描工件获取焊缝在整个焊接路径上的点云数据，利用三次光滑样条算法精确重建搭接焊缝模型；然后利用Douglas-Peucker算法提取焊接路径的关键特征点，计算并优化相应的姿态。在此基础上，建立了将优化后的工艺参数与搭接间隙进行关联的神经网络模型。在焊接过程中，根据模型得到的接头几何形状的变化，自适应调整焊接参数。实验结果表明，该方法对间隙随机分布在0 ~ 2mm的复杂曲线焊缝具有良好的适应性，在路径精度和焊缝外观方面均取得了满意的结果。
Traditional teaching programing for the welding of large-scale complex structures is extremely difficult, with low efficiency and poor consistency, and it is very difficult to obtain the random change of joint geometry and achieve excellent welding quality along the entire welding path. In this paper, an integrated method of automatic generation of welding paths and adaptive filling of lap welding based on laser-structured light scanning is proposed. First, the point-cloud data of the welding joint on the entire welding path were acquired by laser scanning a workpiece, and the welding-seam model of the lap joint was accurately reconstructed using a cubic smoothing spline algorithm. The key feature points of the welding path were then extracted by Douglas-Peucker algorithm and the corresponding postures calculated and optimized. Furthermore, a neural network model that correlated the optimized process parameters with the gaps in the lap joints was established. During the welding process, the welding parameters were adaptively adjusted according to the variation of the obtained joint geometry based on the model. The results of the experiments showed that the proposed method has excellent adaptability to complex-curve welding seams with gaps randomly distributed between 0 and 2 mm, achieving satisfactory results in both path accuracy and weld appearance.